Assignment 11

by Jeremy Boss

HTML

Enter a number between 1 - 6 for the total rainfall at that time (hours)
<input type='text' id='uVal'>
<input type='button' id='calc' value='Find' onclick='calClick()'>
<div id='out'></div>
<div id='out2'></div>

JavaScript

var anArray = [0.00, 0.04, 0.11, 0.60, 0.87, 0.95, 1.00];

function calClick() {
  var val = parseFloat(document.getElementById('uVal').value);
  if (val < 0 || val > 6) {
    return;
  } else {
    var a = Math.floor(val);
    var b = Math.ceil(val);
    if (a == b) {
      document.getElementById('out').innerHTML = "Rainfall at <strong>" + val + "</strong> hour(s): <strong>" + parseFloat(anArray[val] * 100).toFixed(2) + "%</strong>";
      return;
    }

    var y = anArray[a] * 100;
    var z = anArray[b] * 100;
    var o = parseFloat((z - y) / (b - a)).toFixed(2);
    var g = parseFloat(z - (o * b));
    var result = parseFloat((o * val) + g).toFixed(2);
    document.getElementById('out').innerHTML = "Rainfall at <strong>" + val + "</strong> hour(s): <strong>" + result + "%</strong>";
  }
}